This invention relates to solar ponds and more particularly to a method and means of preventing convection of heat in a solar pond. In utilizing a solar pond, it is necessary to suppress or eliminate the upward convection of hot water from the bottom of the pond to the upper pond surface. Such convection allows the inefficient dissipation of heat energy to the atmosphere. Prior solar ponds utilized a salt-gradient to suppress convection. In a salt gradient solar pond, the higher salt concentration at the bottom of the pond makes the hot salty water heavier than the cooler less salty water above it. Convection is thereby suppressed creating a stagnant insulating layer where the destabilizing temperature gradient is overbalanced by the stabilizing salt gradient. Salt gradient solar ponds, however, suffer from two major deficiencies. First, the salt gradient must be maintained as the salt will slowly diffuse to the surface, diminishing the gradient. Also it is possible for outside disturbances to start convecting regions within the insulating layer which seriously decreases the insulating value. Second, salt gradient solar ponds require a lot of salt to maintain stability. Leaks and overflows, as well as pond decommissionings, are potential local and environmental disturbances due to the large amount of salt involved.